Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Dihydro and hexahydro isoalpha acids having a high ratio of trans to cis isomers, production thereof, and products containing the same

a technology of hexahydro isoalpha acids and which is applied in the field of dihydro and hexahydro isoalpha acids having a high production thereof, and products containing the same, can solve the problem that no prior art products have these qualities, and achieve high trans isomer ratio, stable phs, and increased critical ratio of trans to cis isomers

Inactive Publication Date: 2003-06-24
KALAMAZOO HLDG INC
View PDF24 Cites 82 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

This specification discloses DHIA and HHIA having a high ratio of trans to cis isomers and which form clear, non-precipitating aqueous solutions of DHIA and HHIA, both of which are unknown to the prior art. This is due to the heretofore unknown effect of the trans isomers in increasing the solubility of the cis isomers. There is no explanation of this effect, which is contrary to the expectation that higher solute contents decrease solubility of all solutes. This effect is noticed in both neutral and slightly (up to pH 10-11) alkaline water. Because of the improved solubility in relatively low pH aqueous media and beer, the ease of use and utilization in the brewery is vastly improved as compared with the prior art cis products.

Problems solved by technology

None of the prior art products have these qualities.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Dihydro and hexahydro isoalpha acids having a high ratio of trans to cis isomers, production thereof, and products containing the same
  • Dihydro and hexahydro isoalpha acids having a high ratio of trans to cis isomers, production thereof, and products containing the same
  • Dihydro and hexahydro isoalpha acids having a high ratio of trans to cis isomers, production thereof, and products containing the same

Examples

Experimental program
Comparison scheme
Effect test

examples 1 thru 4

show variations on the preferred process for making a high trans , highly soluble DHIA and HHIA which, in turn, do not form hazes upon dilution to 1% in distilled water.

It will be noted that none of these products form insoluble precipitates on standing, and that they may be added directly to soft water to whatever concentration the brewer desires. It will also be noted that they do not form precipitates visible to the unaided eye or measurable haze upon direct injection into bottled beer. None of the prior art products have these qualities. Goldstein's NILUPs-free type DHIA all cis products and the all cis HHIA products presently available do not form clear solutions.

The purity of the hop acids must be exceptionally high if solutions of the high trans product are to remain clear. Substances eluting after the hop acid in the HPLC procedure must be less than 6%, preferably less than 4%, and most preferably less than 1% to 2%. Likewise, "waxes" which do not absorb uv light and which a...

example 1

Preparation of a Liquid DHIA by Reduction Without the Use of Solvent in the Reducing Medium.

52 g of a 29% aqueous solution of IA was added to 100 ml of water and the pH adjusted to 10.5 to improve solubility. 0.87 g of NaBH.sub.4 ( 0.55 molar equivalents ) in 75 ml of water were added, the solution heated to about 50.degree. C., and the reaction terminated after two hours. 50 ml of hexane, a C-6 hydrocarbon, was added, and the mixture cooled. The aqueous and hydrocarbon phases were agitated with phosphoric acid at a pH of 2.8, the aqueous phase containing boron discarded, and the organic phase was extracted with water to remove residual boron. The organic phase, containing the DHIA, was then partitioned against 100 ml of warmed distilled water brought to a pH of 8.4 with potassium hydroxide. (A pH of between about 7.6 to 8.8 is optimal for this separation, although higher and lower pHs may be used. Furthermore, concentrations of 20%, preferably 15%, and most preferably about 10% or ...

example 2

Preparation of DHIA from IA with the Use of Solvent.

500 g of a 25% (measured by total absorbance at 254 nm) aqueous solution of crude IA was added to 250 ml of a 4% solution of NaBH.sub.4 (0.75 molar equivalents). The pH was 11.4. 125ml of limonene, a C-10 hydrocarbon, was added, and the mixture heated with agitation for 3 hours at 70-75.degree. C. The mixture was cooled, and the organic phase separated from the aqueous DHIA phase. The organic phase was discarded. 200 ml of a light petroleum distillate (boiling point less than 100.degree. C.) was added to the aqueous phase, and the solution acidified to pH 2 with phosphoric acid. The aqueous phase was separated and discarded. The organic phase was washed once with water at a pH of about 3, and again at a pH of about 4 to 5 to eliminate all boron. The organic phase was then partitioned with 1000 ml of distilled water brought to a pH of 7.6 with potassium hydroxide and the phases separated. The aqueous DHIA phase was concentrated unde...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

This invention describes heretofore unknown forms of dihydro (DHIA) and hexahydro (HHIA) isoalpha acids having a high ratio of trans to cis isomers and a process for their production. Also, non-precipitating clear 5, 10, 20% and higher aqueous solutions thereof, since they are soluble at room temperature in soft water. This is due to the high ratio of trans to cis isomers. Unlike prior art essentially all cis isomer products, they remain haze free both at a neutral pH in water and at 1% to 2% and higher concentrations. This invention has the advantage over the prior art in that DHIA and HHIA can be provided as stable, non-separating liquids, at practical concentrations in the range of 5% to about 40%, which do not require heating to about 50° to 90° C. and above with stirring to effect dissolution of precipitates. The high trans products described herein can be admixed with isoalpha- and tetrahydro-isoalpha acids.

Description

1. Field of the InventionDihydro and hexahydro isoalpha acids having a high ratio of trans to cis isomers, process for the production thereof, and products containing the same.2. Prior ArtThere are four types of isoalpha acids: the unreduced form, called isoalpha acids (isohumulone) (IA), and three types of reduced forms of IA. The latter are dihydro-isoalpha acids (DHIA), also known as "rho", tetrahydro-isoalpha acids (THIA), and hexahydro-isoalpha acids (HHIA). Each is present as three major analogues differing in an acyl side chain (the co, n, and ad analogues) and as trans and cis and optical isomers. The proportions of analogues depends upon the variety of hops used to make the iso acids. Only IA, DHIA, and THIA have been and are available as aqueous forms. Their structures are shown in FIGS. 1 and 2.IA and THIA do not form insoluble crystalline precipitates upon standing, due to their chemical composition, which includes a keto group on the lower acyl side chain. Commercially ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(United States)
IPC IPC(8): C12C3/00C12C3/08C12C5/00C12C5/02
CPCC12C5/02C12C3/085
Inventor SHAHLAI, KHALILMENNETT, RANDALL H.TODD, PAUL H.GUZINSKI, JAMES A.
Owner KALAMAZOO HLDG INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com